Thread height gauge



Jan. 27, 1942. c, H. ALLEN ETAL THREAD HEIGHT GAUGE Filed Aug. 7, 1940 (Ittorneg Patented Jan. l27, 1942 UNITED STATES PATENT oFrlclrLl n, THREAD HEIGHT GAUGE Charles H. Allen and Rosslyn C. Allen, c

Pittsburgh, Pa.

Application August 7, 1940, Serial No. 351,744-` `1 claim. (c1. 33 199) This invention relates to a gaugaand while primarily designed and intended for ascertaining and indicating variations in the heights or depths, from required standards, cf screw threads in pipes, couplings, ttings, yand the like, it will be obvious that the device may be em*- ployed for any other purposes wherein it is found to be applicable. n l Y Important objects and advantages of the .invention are to provide a gauge of the character described, which is self-centering and self-adjusting, which functions to automatically center itself in rounded top andbottom threads, which embodies an anvil with a shiftable guide sleeve that locates and holds the contact point rexactly in the center of the root of a rounded bottom thread, which maybe readily and conveniently engaged on the product to be measured or re-V moved from the latter, which is simple in its construction and arrangement, durable, compact, attractive in appearance, positive in its action, and economical in its manufacture, operation and maintenance.

With the foregoing and other objects in View, which will appear as the description proceeds, the invention resides inthe novel construction, combination and arrangement of parts herein specifically described and illustrated in theaccompanying drawing, but it is to be understood that changes in the form, proportions, and details of construction may be resorted to that come within the scope of the claim hereunto appended.

In the drawing wherein like numerals ofreference designate corresponding parts throughout the several views:

Figure l is a front elevational view of a thread height gauge constructed in accordance with the invention,and illustrating the application of the device to screw threads. f

Figure 2 is a side elevational view of the anvil and associated parts embodied in the present invention.

Figure 3 is an enlarged front view, partly in cross section, of the anvil and of parts disposed within the latter.

Figure 4 is a side View of the guide sleeve.

Referring in detail to the drawing I denotes an anvil in its entirety. The anvil is an integral structure embodying an elongated, horizontally disposed seating block 2, a spacing shank 3 extending vertically upward from the seating block, and a connecting saddle 4 carried at the upper end of the shank. The seating block and the connecting saddle are illustrated as extending in the same general directions, but it will'here be noted that the anvil is=a1so being constructed with the` seatingblock disposedl at right angles to the disposition of ,said connecting saddle.

The anvil I is provided with a comparatively large bore A5, which extends vertically through the seating block 2, through the spacing shank 3, and through the connecting saddle 4. The bore is open at both ends and the lower portion thereof is reduced as indicated at 6, Ato provide a seating shoulder 1 located withinv theA seating .block of the anvil structure. f

A dial indicator 8, of any suitable conventional construction nowin common use, is rigidly secured on the top of the anvilconnecting saddle 4 by means of screws 9, or in any other suitable manner. The indicator has a dial displaying scale graduations, each of which latter represents one one-,thousandth of an inch. 'Ihe indicator includes la spring controlled actuatingr rod I0, and a fixed bearingl for the latter indicated at II. l The bearing depends into the anvil bore 5, and the actuating rod projects beyond the lower free end of saidbearing.

A most important feature of the invention resides in the provision and function of a guide sleeve I2, which is mounted for vertically shiftable movement in the anvil bore 5. The guide sleeve is formed with a comparatively large pocket portion I3, an intermediate guide portion I4, and a tapered lower portion I5.

The relative diameters of the pocket and guide portions I3 and I4, of the sleeve guide I2, provide ashoulder offset I6 between saidportions seating on the* shoulder I formed in the wall of the anvil bore 5 in themanner hereinbefore set forth.

The pocket portion I3 is formed with a comparatively large pocket I 'I to provide clearance permitting the entrance of the lower end of the actuating lrod, I0 therein, during the operation of the device in the manner to be described.

A guide passage I8, opening into the pocket I1, extends vertically through the guide and tan pered portions I4 and I5, of the guide sleeve I2. A contact pin I9 is shiftably extended through the passage I8, and has its upper end secured in the lower end of the actuating rod IU by a screw thread connection, as shown, or in any other suitable manner. The contact pin has a tapered contact point I9', which normally projects through and beyond the lower free end of the tapered portion I5 of the guide sleeve I2.

A spiral spring 20 is mounted in the anvil bore 5 and surrounds the projecting end of the actu ating rod ID of the indicator 8. The upper end of the spring abuts against the lower end of the bearing II, and the lower end thereof rests against the top edge oi the guide sleeve I2, as clearly illustrated in Figure 3. The action of the spring normally maintains the sleeve offset I6 seated on the shoulder 1, whereby the tapered portion I5, of the guide sleeve I2, projects through the bore portion 6 and beyond the bottom face of the anvil seating block 2. The guide sleeve I2 is shiftable in the anvil bore, against the action of the spring, to fully retract the normally projecting tapered portion I5 thereof to within the anvil bore.

The seating block 2 of the anvil I is formed with' tapered side walls 2 I, which latter converge downwardly to provide a rounded bottom 22 adapted for seating on the screw threads 23 of the work 24 to be gauged by use of thedevice.

As stated, the tapered portion I5, of the guide sleeve I2, is normally projected throughV the bore portion 6 and beyond the face of the rounded bottom 22 of the anvil I'by the Aaction of the spring 20, The contact point I9 ofthe Contact pin I9 likewise is normally projected through the sleeve passage I8 and .beyond the tapered outer end of said sleeve by the action of the) spring controlled actuating rod I0 of the dial indicator- 8. It will here be noted that the permitted movements of the guide sleeve I2and of the contact pin I9 are -entirely independent oi each other, and that both said sleeve and Contact pin may be repressed to retract same fully within the anvil structure. Prior to use, the indicator 8 is so calibrated that the permitted projection of the contact pin point I9 is such that whenthe latter rest properly on the bottom of adjacent threads of adjacent thread convolutions of proper heights, the dial indicator will register zero Any variations from the proper height or depth of the threads will obviously be registered by the indicator dueto the retraction or projection of the contact pin to variations of the calibrated standard of the indicator. v Y

In gauging threads, the seating block 2, of the anvil I, is placed across the threads 23, as shown in Figure 1, and the Whole gauge structure is positioned in radial alignment relatively to the axis of the work 24. Due to the rounded bottom 22, of the seating block, the proper positioning of the device on the work is conveniently and readily effected and greatly facilitated.

As herein stated, the important feature of the invention is the function of the guide sleeve I2. When the seating block 2 is placed across the threads, the tapered portion I5, of the sleeve I2, will automatically be forced, by the action of the spring 20, into the widest space between adjacent thread convolutions, and thereby centralizes the pin contact point I9' to locate and hold scribed, the combination with an indicator including an actuating member, of an anvil provided with a bore secured to the indicator, a spring controlled guide sleeve shiftably seated in said bore, said sleeve having a tapered portion normally projecting beyond the bottom of said anvil, a contactelement carried Ybysaid member andextending through saidy sleeve, the free end of lsaidvelement normally projecting beyond the portion of said sleeve.

free end of said tapered n A CHARLES H. ALLEN.

RQSSLYN C. ALLEN. 

